Helen Maitland, Colmonell, Ayrshire mid 1700's

I've hit a brick wall in my tree with Helen Maitland who married Robert Eglesham (Eaglesham)in Colmonell around 1770.This date was supplied to me by another person but I have not been able to confirm it through the LDS site or old parish registers so don't know where it originated. She was born abt 1750.Does anyone have any reliable information to confirm this?I'm also trying to find her parent information.